8244593: Clean up GNM/NM after JEP 381

Reviewed-by: erikj

make/autoconf/compare.sh.in

@@ -53,7 +53,7 @@ export LDD="@LDD@"
 export LN="@LN@"
 export MKDIR="@MKDIR@"
 export MV="@MV@"
-export NM="@GNM@"
+export NM="@NM@"
 export OBJDUMP="@OBJDUMP@"
 export OTOOL="@OTOOL@"
 export PRINTF="@PRINTF@"

make/autoconf/spec.gmk.in

@@ -582,7 +582,6 @@ AR := @AR@
 ARFLAGS:=@ARFLAGS@
 
 NM:=@NM@
-GNM:=@GNM@
 STRIP:=@STRIP@
 OBJDUMP:=@OBJDUMP@
 CXXFILT:=@CXXFILT@

make/autoconf/toolchain.m4

@@ -772,8 +772,6 @@ AC_DEFUN_ONCE([TOOLCHAIN_DETECT_TOOLCHAIN_EXTRA],
     else
       UTIL_LOOKUP_TOOLCHAIN_PROGS(NM, nm)
     fi
-    GNM="$NM"
-    AC_SUBST(GNM)
   fi
 
   # objcopy is used for moving debug symbols to separate files when